| 1 | /* |
| 2 | * Event char devices, giving access to raw input device events. |
| 3 | * |
| 4 | * Copyright (c) 1999-2002 Vojtech Pavlik |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License version 2 as published by |
| 8 | * the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 12 | |
| 13 | #define EVDEV_MINOR_BASE 64 |
| 14 | #define EVDEV_MINORS 32 |
| 15 | #define EVDEV_MIN_BUFFER_SIZE 64U |
| 16 | #define EVDEV_BUF_PACKETS 8 |
| 17 | |
| 18 | #include <linux/poll.h> |
| 19 | #include <linux/sched.h> |
| 20 | #include <linux/slab.h> |
| 21 | #include <linux/vmalloc.h> |
| 22 | #include <linux/mm.h> |
| 23 | #include <linux/module.h> |
| 24 | #include <linux/init.h> |
| 25 | #include <linux/input/mt.h> |
| 26 | #include <linux/major.h> |
| 27 | #include <linux/device.h> |
| 28 | #include <linux/cdev.h> |
| 29 | #include "input-compat.h" |
| 30 | |
| 31 | enum evdev_clock_type { |
| 32 | EV_CLK_REAL = 0, |
| 33 | EV_CLK_MONO, |
| 34 | EV_CLK_BOOT, |
| 35 | EV_CLK_MAX |
| 36 | }; |
| 37 | |
| 38 | struct evdev { |
| 39 | int open; |
| 40 | struct input_handle handle; |
| 41 | wait_queue_head_t wait; |
| 42 | struct evdev_client __rcu *grab; |
| 43 | struct list_head client_list; |
| 44 | spinlock_t client_lock; /* protects client_list */ |
| 45 | struct mutex mutex; |
| 46 | struct device dev; |
| 47 | struct cdev cdev; |
| 48 | bool exist; |
| 49 | }; |
| 50 | |
| 51 | struct evdev_client { |
| 52 | unsigned int head; |
| 53 | unsigned int tail; |
| 54 | unsigned int packet_head; /* [future] position of the first element of next packet */ |
| 55 | spinlock_t buffer_lock; /* protects access to buffer, head and tail */ |
| 56 | struct fasync_struct *fasync; |
| 57 | struct evdev *evdev; |
| 58 | struct list_head node; |
| 59 | unsigned int clk_type; |
| 60 | bool revoked; |
| 61 | unsigned long *evmasks[EV_CNT]; |
| 62 | unsigned int bufsize; |
| 63 | struct input_event buffer[]; |
| 64 | }; |
| 65 | |
| 66 | static size_t evdev_get_mask_cnt(unsigned int type) |
| 67 | { |
| 68 | static const size_t counts[EV_CNT] = { |
| 69 | /* EV_SYN==0 is EV_CNT, _not_ SYN_CNT, see EVIOCGBIT */ |
| 70 | [EV_SYN] = EV_CNT, |
| 71 | [EV_KEY] = KEY_CNT, |
| 72 | [EV_REL] = REL_CNT, |
| 73 | [EV_ABS] = ABS_CNT, |
| 74 | [EV_MSC] = MSC_CNT, |
| 75 | [EV_SW] = SW_CNT, |
| 76 | [EV_LED] = LED_CNT, |
| 77 | [EV_SND] = SND_CNT, |
| 78 | [EV_FF] = FF_CNT, |
| 79 | }; |
| 80 | |
| 81 | return (type < EV_CNT) ? counts[type] : 0; |
| 82 | } |
| 83 | |
| 84 | /* requires the buffer lock to be held */ |
| 85 | static bool __evdev_is_filtered(struct evdev_client *client, |
| 86 | unsigned int type, |
| 87 | unsigned int code) |
| 88 | { |
| 89 | unsigned long *mask; |
| 90 | size_t cnt; |
| 91 | |
| 92 | /* EV_SYN and unknown codes are never filtered */ |
| 93 | if (type == EV_SYN || type >= EV_CNT) |
| 94 | return false; |
| 95 | |
| 96 | /* first test whether the type is filtered */ |
| 97 | mask = client->evmasks[0]; |
| 98 | if (mask && !test_bit(type, mask)) |
| 99 | return true; |
| 100 | |
| 101 | /* unknown values are never filtered */ |
| 102 | cnt = evdev_get_mask_cnt(type); |
| 103 | if (!cnt || code >= cnt) |
| 104 | return false; |
| 105 | |
| 106 | mask = client->evmasks[type]; |
| 107 | return mask && !test_bit(code, mask); |
| 108 | } |
| 109 | |
| 110 | /* flush queued events of type @type, caller must hold client->buffer_lock */ |
| 111 | static void __evdev_flush_queue(struct evdev_client *client, unsigned int type) |
| 112 | { |
| 113 | unsigned int i, head, num; |
| 114 | unsigned int mask = client->bufsize - 1; |
| 115 | bool is_report; |
| 116 | struct input_event *ev; |
| 117 | |
| 118 | BUG_ON(type == EV_SYN); |
| 119 | |
| 120 | head = client->tail; |
| 121 | client->packet_head = client->tail; |
| 122 | |
| 123 | /* init to 1 so a leading SYN_REPORT will not be dropped */ |
| 124 | num = 1; |
| 125 | |
| 126 | for (i = client->tail; i != client->head; i = (i + 1) & mask) { |
| 127 | ev = &client->buffer[i]; |
| 128 | is_report = ev->type == EV_SYN && ev->code == SYN_REPORT; |
| 129 | |
| 130 | if (ev->type == type) { |
| 131 | /* drop matched entry */ |
| 132 | continue; |
| 133 | } else if (is_report && !num) { |
| 134 | /* drop empty SYN_REPORT groups */ |
| 135 | continue; |
| 136 | } else if (head != i) { |
| 137 | /* move entry to fill the gap */ |
| 138 | client->buffer[head].time = ev->time; |
| 139 | client->buffer[head].type = ev->type; |
| 140 | client->buffer[head].code = ev->code; |
| 141 | client->buffer[head].value = ev->value; |
| 142 | } |
| 143 | |
| 144 | num++; |
| 145 | head = (head + 1) & mask; |
| 146 | |
| 147 | if (is_report) { |
| 148 | num = 0; |
| 149 | client->packet_head = head; |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | client->head = head; |
| 154 | } |
| 155 | |
| 156 | static void __evdev_queue_syn_dropped(struct evdev_client *client) |
| 157 | { |
| 158 | struct input_event ev; |
| 159 | ktime_t time; |
| 160 | |
| 161 | time = client->clk_type == EV_CLK_REAL ? |
| 162 | ktime_get_real() : |
| 163 | client->clk_type == EV_CLK_MONO ? |
| 164 | ktime_get() : |
| 165 | ktime_get_boottime(); |
| 166 | |
| 167 | ev.time = ktime_to_timeval(time); |
| 168 | ev.type = EV_SYN; |
| 169 | ev.code = SYN_DROPPED; |
| 170 | ev.value = 0; |
| 171 | |
| 172 | client->buffer[client->head++] = ev; |
| 173 | client->head &= client->bufsize - 1; |
| 174 | |
| 175 | if (unlikely(client->head == client->tail)) { |
| 176 | /* drop queue but keep our SYN_DROPPED event */ |
| 177 | client->tail = (client->head - 1) & (client->bufsize - 1); |
| 178 | client->packet_head = client->tail; |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | static void evdev_queue_syn_dropped(struct evdev_client *client) |
| 183 | { |
| 184 | unsigned long flags; |
| 185 | |
| 186 | spin_lock_irqsave(&client->buffer_lock, flags); |
| 187 | __evdev_queue_syn_dropped(client); |
| 188 | spin_unlock_irqrestore(&client->buffer_lock, flags); |
| 189 | } |
| 190 | |
| 191 | static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid) |
| 192 | { |
| 193 | unsigned long flags; |
| 194 | unsigned int clk_type; |
| 195 | |
| 196 | switch (clkid) { |
| 197 | |
| 198 | case CLOCK_REALTIME: |
| 199 | clk_type = EV_CLK_REAL; |
| 200 | break; |
| 201 | case CLOCK_MONOTONIC: |
| 202 | clk_type = EV_CLK_MONO; |
| 203 | break; |
| 204 | case CLOCK_BOOTTIME: |
| 205 | clk_type = EV_CLK_BOOT; |
| 206 | break; |
| 207 | default: |
| 208 | return -EINVAL; |
| 209 | } |
| 210 | |
| 211 | if (client->clk_type != clk_type) { |
| 212 | client->clk_type = clk_type; |
| 213 | |
| 214 | /* |
| 215 | * Flush pending events and queue SYN_DROPPED event, |
| 216 | * but only if the queue is not empty. |
| 217 | */ |
| 218 | spin_lock_irqsave(&client->buffer_lock, flags); |
| 219 | |
| 220 | if (client->head != client->tail) { |
| 221 | client->packet_head = client->head = client->tail; |
| 222 | __evdev_queue_syn_dropped(client); |
| 223 | } |
| 224 | |
| 225 | spin_unlock_irqrestore(&client->buffer_lock, flags); |
| 226 | } |
| 227 | |
| 228 | return 0; |
| 229 | } |
| 230 | |
| 231 | static void __pass_event(struct evdev_client *client, |
| 232 | const struct input_event *event) |
| 233 | { |
| 234 | client->buffer[client->head++] = *event; |
| 235 | client->head &= client->bufsize - 1; |
| 236 | |
| 237 | if (unlikely(client->head == client->tail)) { |
| 238 | /* |
| 239 | * This effectively "drops" all unconsumed events, leaving |
| 240 | * EV_SYN/SYN_DROPPED plus the newest event in the queue. |
| 241 | */ |
| 242 | client->tail = (client->head - 2) & (client->bufsize - 1); |
| 243 | |
| 244 | client->buffer[client->tail].time = event->time; |
| 245 | client->buffer[client->tail].type = EV_SYN; |
| 246 | client->buffer[client->tail].code = SYN_DROPPED; |
| 247 | client->buffer[client->tail].value = 0; |
| 248 | |
| 249 | client->packet_head = client->tail; |
| 250 | } |
| 251 | |
| 252 | if (event->type == EV_SYN && event->code == SYN_REPORT) { |
| 253 | client->packet_head = client->head; |
| 254 | kill_fasync(&client->fasync, SIGIO, POLL_IN); |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | static void evdev_pass_values(struct evdev_client *client, |
| 259 | const struct input_value *vals, unsigned int count, |
| 260 | ktime_t *ev_time) |
| 261 | { |
| 262 | struct evdev *evdev = client->evdev; |
| 263 | const struct input_value *v; |
| 264 | struct input_event event; |
| 265 | bool wakeup = false; |
| 266 | |
| 267 | if (client->revoked) |
| 268 | return; |
| 269 | |
| 270 | event.time = ktime_to_timeval(ev_time[client->clk_type]); |
| 271 | |
| 272 | /* Interrupts are disabled, just acquire the lock. */ |
| 273 | spin_lock(&client->buffer_lock); |
| 274 | |
| 275 | for (v = vals; v != vals + count; v++) { |
| 276 | if (__evdev_is_filtered(client, v->type, v->code)) |
| 277 | continue; |
| 278 | |
| 279 | if (v->type == EV_SYN && v->code == SYN_REPORT) { |
| 280 | /* drop empty SYN_REPORT */ |
| 281 | if (client->packet_head == client->head) |
| 282 | continue; |
| 283 | |
| 284 | wakeup = true; |
| 285 | } |
| 286 | |
| 287 | event.type = v->type; |
| 288 | event.code = v->code; |
| 289 | event.value = v->value; |
| 290 | __pass_event(client, &event); |
| 291 | } |
| 292 | |
| 293 | spin_unlock(&client->buffer_lock); |
| 294 | |
| 295 | if (wakeup) |
| 296 | wake_up_interruptible(&evdev->wait); |
| 297 | } |
| 298 | |
| 299 | /* |
| 300 | * Pass incoming events to all connected clients. |
| 301 | */ |
| 302 | static void evdev_events(struct input_handle *handle, |
| 303 | const struct input_value *vals, unsigned int count) |
| 304 | { |
| 305 | struct evdev *evdev = handle->private; |
| 306 | struct evdev_client *client; |
| 307 | ktime_t ev_time[EV_CLK_MAX]; |
| 308 | |
| 309 | ev_time[EV_CLK_MONO] = ktime_get(); |
| 310 | ev_time[EV_CLK_REAL] = ktime_mono_to_real(ev_time[EV_CLK_MONO]); |
| 311 | ev_time[EV_CLK_BOOT] = ktime_mono_to_any(ev_time[EV_CLK_MONO], |
| 312 | TK_OFFS_BOOT); |
| 313 | |
| 314 | rcu_read_lock(); |
| 315 | |
| 316 | client = rcu_dereference(evdev->grab); |
| 317 | |
| 318 | if (client) |
| 319 | evdev_pass_values(client, vals, count, ev_time); |
| 320 | else |
| 321 | list_for_each_entry_rcu(client, &evdev->client_list, node) |
| 322 | evdev_pass_values(client, vals, count, ev_time); |
| 323 | |
| 324 | rcu_read_unlock(); |
| 325 | } |
| 326 | |
| 327 | /* |
| 328 | * Pass incoming event to all connected clients. |
| 329 | */ |
| 330 | static void evdev_event(struct input_handle *handle, |
| 331 | unsigned int type, unsigned int code, int value) |
| 332 | { |
| 333 | struct input_value vals[] = { { type, code, value } }; |
| 334 | |
| 335 | evdev_events(handle, vals, 1); |
| 336 | } |
| 337 | |
| 338 | static int evdev_fasync(int fd, struct file *file, int on) |
| 339 | { |
| 340 | struct evdev_client *client = file->private_data; |
| 341 | |
| 342 | return fasync_helper(fd, file, on, &client->fasync); |
| 343 | } |
| 344 | |
| 345 | static int evdev_flush(struct file *file, fl_owner_t id) |
| 346 | { |
| 347 | struct evdev_client *client = file->private_data; |
| 348 | struct evdev *evdev = client->evdev; |
| 349 | |
| 350 | mutex_lock(&evdev->mutex); |
| 351 | |
| 352 | if (evdev->exist && !client->revoked) |
| 353 | input_flush_device(&evdev->handle, file); |
| 354 | |
| 355 | mutex_unlock(&evdev->mutex); |
| 356 | return 0; |
| 357 | } |
| 358 | |
| 359 | static void evdev_free(struct device *dev) |
| 360 | { |
| 361 | struct evdev *evdev = container_of(dev, struct evdev, dev); |
| 362 | |
| 363 | input_put_device(evdev->handle.dev); |
| 364 | kfree(evdev); |
| 365 | } |
| 366 | |
| 367 | /* |
| 368 | * Grabs an event device (along with underlying input device). |
| 369 | * This function is called with evdev->mutex taken. |
| 370 | */ |
| 371 | static int evdev_grab(struct evdev *evdev, struct evdev_client *client) |
| 372 | { |
| 373 | int error; |
| 374 | |
| 375 | if (evdev->grab) |
| 376 | return -EBUSY; |
| 377 | |
| 378 | error = input_grab_device(&evdev->handle); |
| 379 | if (error) |
| 380 | return error; |
| 381 | |
| 382 | rcu_assign_pointer(evdev->grab, client); |
| 383 | |
| 384 | return 0; |
| 385 | } |
| 386 | |
| 387 | static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) |
| 388 | { |
| 389 | struct evdev_client *grab = rcu_dereference_protected(evdev->grab, |
| 390 | lockdep_is_held(&evdev->mutex)); |
| 391 | |
| 392 | if (grab != client) |
| 393 | return -EINVAL; |
| 394 | |
| 395 | rcu_assign_pointer(evdev->grab, NULL); |
| 396 | synchronize_rcu(); |
| 397 | input_release_device(&evdev->handle); |
| 398 | |
| 399 | return 0; |
| 400 | } |
| 401 | |
| 402 | static void evdev_attach_client(struct evdev *evdev, |
| 403 | struct evdev_client *client) |
| 404 | { |
| 405 | spin_lock(&evdev->client_lock); |
| 406 | list_add_tail_rcu(&client->node, &evdev->client_list); |
| 407 | spin_unlock(&evdev->client_lock); |
| 408 | } |
| 409 | |
| 410 | static void evdev_detach_client(struct evdev *evdev, |
| 411 | struct evdev_client *client) |
| 412 | { |
| 413 | spin_lock(&evdev->client_lock); |
| 414 | list_del_rcu(&client->node); |
| 415 | spin_unlock(&evdev->client_lock); |
| 416 | synchronize_rcu(); |
| 417 | } |
| 418 | |
| 419 | static int evdev_open_device(struct evdev *evdev) |
| 420 | { |
| 421 | int retval; |
| 422 | |
| 423 | retval = mutex_lock_interruptible(&evdev->mutex); |
| 424 | if (retval) |
| 425 | return retval; |
| 426 | |
| 427 | if (!evdev->exist) |
| 428 | retval = -ENODEV; |
| 429 | else if (!evdev->open++) { |
| 430 | retval = input_open_device(&evdev->handle); |
| 431 | if (retval) |
| 432 | evdev->open--; |
| 433 | } |
| 434 | |
| 435 | mutex_unlock(&evdev->mutex); |
| 436 | return retval; |
| 437 | } |
| 438 | |
| 439 | static void evdev_close_device(struct evdev *evdev) |
| 440 | { |
| 441 | mutex_lock(&evdev->mutex); |
| 442 | |
| 443 | if (evdev->exist && !--evdev->open) |
| 444 | input_close_device(&evdev->handle); |
| 445 | |
| 446 | mutex_unlock(&evdev->mutex); |
| 447 | } |
| 448 | |
| 449 | /* |
| 450 | * Wake up users waiting for IO so they can disconnect from |
| 451 | * dead device. |
| 452 | */ |
| 453 | static void evdev_hangup(struct evdev *evdev) |
| 454 | { |
| 455 | struct evdev_client *client; |
| 456 | |
| 457 | spin_lock(&evdev->client_lock); |
| 458 | list_for_each_entry(client, &evdev->client_list, node) |
| 459 | kill_fasync(&client->fasync, SIGIO, POLL_HUP); |
| 460 | spin_unlock(&evdev->client_lock); |
| 461 | |
| 462 | wake_up_interruptible(&evdev->wait); |
| 463 | } |
| 464 | |
| 465 | static int evdev_release(struct inode *inode, struct file *file) |
| 466 | { |
| 467 | struct evdev_client *client = file->private_data; |
| 468 | struct evdev *evdev = client->evdev; |
| 469 | unsigned int i; |
| 470 | |
| 471 | mutex_lock(&evdev->mutex); |
| 472 | evdev_ungrab(evdev, client); |
| 473 | mutex_unlock(&evdev->mutex); |
| 474 | |
| 475 | evdev_detach_client(evdev, client); |
| 476 | |
| 477 | for (i = 0; i < EV_CNT; ++i) |
| 478 | kfree(client->evmasks[i]); |
| 479 | |
| 480 | kvfree(client); |
| 481 | |
| 482 | evdev_close_device(evdev); |
| 483 | |
| 484 | return 0; |
| 485 | } |
| 486 | |
| 487 | static unsigned int evdev_compute_buffer_size(struct input_dev *dev) |
| 488 | { |
| 489 | unsigned int n_events = |
| 490 | max(dev->hint_events_per_packet * EVDEV_BUF_PACKETS, |
| 491 | EVDEV_MIN_BUFFER_SIZE); |
| 492 | |
| 493 | return roundup_pow_of_two(n_events); |
| 494 | } |
| 495 | |
| 496 | static int evdev_open(struct inode *inode, struct file *file) |
| 497 | { |
| 498 | struct evdev *evdev = container_of(inode->i_cdev, struct evdev, cdev); |
| 499 | unsigned int bufsize = evdev_compute_buffer_size(evdev->handle.dev); |
| 500 | unsigned int size = sizeof(struct evdev_client) + |
| 501 | bufsize * sizeof(struct input_event); |
| 502 | struct evdev_client *client; |
| 503 | int error; |
| 504 | |
| 505 | client = kzalloc(size, GFP_KERNEL | __GFP_NOWARN); |
| 506 | if (!client) |
| 507 | client = vzalloc(size); |
| 508 | if (!client) |
| 509 | return -ENOMEM; |
| 510 | |
| 511 | client->bufsize = bufsize; |
| 512 | spin_lock_init(&client->buffer_lock); |
| 513 | client->evdev = evdev; |
| 514 | evdev_attach_client(evdev, client); |
| 515 | |
| 516 | error = evdev_open_device(evdev); |
| 517 | if (error) |
| 518 | goto err_free_client; |
| 519 | |
| 520 | file->private_data = client; |
| 521 | nonseekable_open(inode, file); |
| 522 | |
| 523 | return 0; |
| 524 | |
| 525 | err_free_client: |
| 526 | evdev_detach_client(evdev, client); |
| 527 | kvfree(client); |
| 528 | return error; |
| 529 | } |
| 530 | |
| 531 | static ssize_t evdev_write(struct file *file, const char __user *buffer, |
| 532 | size_t count, loff_t *ppos) |
| 533 | { |
| 534 | struct evdev_client *client = file->private_data; |
| 535 | struct evdev *evdev = client->evdev; |
| 536 | struct input_event event; |
| 537 | int retval = 0; |
| 538 | |
| 539 | if (count != 0 && count < input_event_size()) |
| 540 | return -EINVAL; |
| 541 | |
| 542 | retval = mutex_lock_interruptible(&evdev->mutex); |
| 543 | if (retval) |
| 544 | return retval; |
| 545 | |
| 546 | if (!evdev->exist || client->revoked) { |
| 547 | retval = -ENODEV; |
| 548 | goto out; |
| 549 | } |
| 550 | |
| 551 | while (retval + input_event_size() <= count) { |
| 552 | |
| 553 | if (input_event_from_user(buffer + retval, &event)) { |
| 554 | retval = -EFAULT; |
| 555 | goto out; |
| 556 | } |
| 557 | retval += input_event_size(); |
| 558 | |
| 559 | input_inject_event(&evdev->handle, |
| 560 | event.type, event.code, event.value); |
| 561 | } |
| 562 | |
| 563 | out: |
| 564 | mutex_unlock(&evdev->mutex); |
| 565 | return retval; |
| 566 | } |
| 567 | |
| 568 | static int evdev_fetch_next_event(struct evdev_client *client, |
| 569 | struct input_event *event) |
| 570 | { |
| 571 | int have_event; |
| 572 | |
| 573 | spin_lock_irq(&client->buffer_lock); |
| 574 | |
| 575 | have_event = client->packet_head != client->tail; |
| 576 | if (have_event) { |
| 577 | *event = client->buffer[client->tail++]; |
| 578 | client->tail &= client->bufsize - 1; |
| 579 | } |
| 580 | |
| 581 | spin_unlock_irq(&client->buffer_lock); |
| 582 | |
| 583 | return have_event; |
| 584 | } |
| 585 | |
| 586 | static ssize_t evdev_read(struct file *file, char __user *buffer, |
| 587 | size_t count, loff_t *ppos) |
| 588 | { |
| 589 | struct evdev_client *client = file->private_data; |
| 590 | struct evdev *evdev = client->evdev; |
| 591 | struct input_event event; |
| 592 | size_t read = 0; |
| 593 | int error; |
| 594 | |
| 595 | if (count != 0 && count < input_event_size()) |
| 596 | return -EINVAL; |
| 597 | |
| 598 | for (;;) { |
| 599 | if (!evdev->exist || client->revoked) |
| 600 | return -ENODEV; |
| 601 | |
| 602 | if (client->packet_head == client->tail && |
| 603 | (file->f_flags & O_NONBLOCK)) |
| 604 | return -EAGAIN; |
| 605 | |
| 606 | /* |
| 607 | * count == 0 is special - no IO is done but we check |
| 608 | * for error conditions (see above). |
| 609 | */ |
| 610 | if (count == 0) |
| 611 | break; |
| 612 | |
| 613 | while (read + input_event_size() <= count && |
| 614 | evdev_fetch_next_event(client, &event)) { |
| 615 | |
| 616 | if (input_event_to_user(buffer + read, &event)) |
| 617 | return -EFAULT; |
| 618 | |
| 619 | read += input_event_size(); |
| 620 | } |
| 621 | |
| 622 | if (read) |
| 623 | break; |
| 624 | |
| 625 | if (!(file->f_flags & O_NONBLOCK)) { |
| 626 | error = wait_event_interruptible(evdev->wait, |
| 627 | client->packet_head != client->tail || |
| 628 | !evdev->exist || client->revoked); |
| 629 | if (error) |
| 630 | return error; |
| 631 | } |
| 632 | } |
| 633 | |
| 634 | return read; |
| 635 | } |
| 636 | |
| 637 | /* No kernel lock - fine */ |
| 638 | static unsigned int evdev_poll(struct file *file, poll_table *wait) |
| 639 | { |
| 640 | struct evdev_client *client = file->private_data; |
| 641 | struct evdev *evdev = client->evdev; |
| 642 | unsigned int mask; |
| 643 | |
| 644 | poll_wait(file, &evdev->wait, wait); |
| 645 | |
| 646 | if (evdev->exist && !client->revoked) |
| 647 | mask = POLLOUT | POLLWRNORM; |
| 648 | else |
| 649 | mask = POLLHUP | POLLERR; |
| 650 | |
| 651 | if (client->packet_head != client->tail) |
| 652 | mask |= POLLIN | POLLRDNORM; |
| 653 | |
| 654 | return mask; |
| 655 | } |
| 656 | |
| 657 | #ifdef CONFIG_COMPAT |
| 658 | |
| 659 | #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) |
| 660 | #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) |
| 661 | |
| 662 | #ifdef __BIG_ENDIAN |
| 663 | static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| 664 | unsigned int maxlen, void __user *p, int compat) |
| 665 | { |
| 666 | int len, i; |
| 667 | |
| 668 | if (compat) { |
| 669 | len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); |
| 670 | if (len > maxlen) |
| 671 | len = maxlen; |
| 672 | |
| 673 | for (i = 0; i < len / sizeof(compat_long_t); i++) |
| 674 | if (copy_to_user((compat_long_t __user *) p + i, |
| 675 | (compat_long_t *) bits + |
| 676 | i + 1 - ((i % 2) << 1), |
| 677 | sizeof(compat_long_t))) |
| 678 | return -EFAULT; |
| 679 | } else { |
| 680 | len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| 681 | if (len > maxlen) |
| 682 | len = maxlen; |
| 683 | |
| 684 | if (copy_to_user(p, bits, len)) |
| 685 | return -EFAULT; |
| 686 | } |
| 687 | |
| 688 | return len; |
| 689 | } |
| 690 | |
| 691 | static int bits_from_user(unsigned long *bits, unsigned int maxbit, |
| 692 | unsigned int maxlen, const void __user *p, int compat) |
| 693 | { |
| 694 | int len, i; |
| 695 | |
| 696 | if (compat) { |
| 697 | if (maxlen % sizeof(compat_long_t)) |
| 698 | return -EINVAL; |
| 699 | |
| 700 | len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); |
| 701 | if (len > maxlen) |
| 702 | len = maxlen; |
| 703 | |
| 704 | for (i = 0; i < len / sizeof(compat_long_t); i++) |
| 705 | if (copy_from_user((compat_long_t *) bits + |
| 706 | i + 1 - ((i % 2) << 1), |
| 707 | (compat_long_t __user *) p + i, |
| 708 | sizeof(compat_long_t))) |
| 709 | return -EFAULT; |
| 710 | if (i % 2) |
| 711 | *((compat_long_t *) bits + i - 1) = 0; |
| 712 | |
| 713 | } else { |
| 714 | if (maxlen % sizeof(long)) |
| 715 | return -EINVAL; |
| 716 | |
| 717 | len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| 718 | if (len > maxlen) |
| 719 | len = maxlen; |
| 720 | |
| 721 | if (copy_from_user(bits, p, len)) |
| 722 | return -EFAULT; |
| 723 | } |
| 724 | |
| 725 | return len; |
| 726 | } |
| 727 | |
| 728 | #else |
| 729 | |
| 730 | static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| 731 | unsigned int maxlen, void __user *p, int compat) |
| 732 | { |
| 733 | int len = compat ? |
| 734 | BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) : |
| 735 | BITS_TO_LONGS(maxbit) * sizeof(long); |
| 736 | |
| 737 | if (len > maxlen) |
| 738 | len = maxlen; |
| 739 | |
| 740 | return copy_to_user(p, bits, len) ? -EFAULT : len; |
| 741 | } |
| 742 | |
| 743 | static int bits_from_user(unsigned long *bits, unsigned int maxbit, |
| 744 | unsigned int maxlen, const void __user *p, int compat) |
| 745 | { |
| 746 | size_t chunk_size = compat ? sizeof(compat_long_t) : sizeof(long); |
| 747 | int len; |
| 748 | |
| 749 | if (maxlen % chunk_size) |
| 750 | return -EINVAL; |
| 751 | |
| 752 | len = compat ? BITS_TO_LONGS_COMPAT(maxbit) : BITS_TO_LONGS(maxbit); |
| 753 | len *= chunk_size; |
| 754 | if (len > maxlen) |
| 755 | len = maxlen; |
| 756 | |
| 757 | return copy_from_user(bits, p, len) ? -EFAULT : len; |
| 758 | } |
| 759 | |
| 760 | #endif /* __BIG_ENDIAN */ |
| 761 | |
| 762 | #else |
| 763 | |
| 764 | static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| 765 | unsigned int maxlen, void __user *p, int compat) |
| 766 | { |
| 767 | int len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| 768 | |
| 769 | if (len > maxlen) |
| 770 | len = maxlen; |
| 771 | |
| 772 | return copy_to_user(p, bits, len) ? -EFAULT : len; |
| 773 | } |
| 774 | |
| 775 | static int bits_from_user(unsigned long *bits, unsigned int maxbit, |
| 776 | unsigned int maxlen, const void __user *p, int compat) |
| 777 | { |
| 778 | int len; |
| 779 | |
| 780 | if (maxlen % sizeof(long)) |
| 781 | return -EINVAL; |
| 782 | |
| 783 | len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| 784 | if (len > maxlen) |
| 785 | len = maxlen; |
| 786 | |
| 787 | return copy_from_user(bits, p, len) ? -EFAULT : len; |
| 788 | } |
| 789 | |
| 790 | #endif /* CONFIG_COMPAT */ |
| 791 | |
| 792 | static int str_to_user(const char *str, unsigned int maxlen, void __user *p) |
| 793 | { |
| 794 | int len; |
| 795 | |
| 796 | if (!str) |
| 797 | return -ENOENT; |
| 798 | |
| 799 | len = strlen(str) + 1; |
| 800 | if (len > maxlen) |
| 801 | len = maxlen; |
| 802 | |
| 803 | return copy_to_user(p, str, len) ? -EFAULT : len; |
| 804 | } |
| 805 | |
| 806 | static int handle_eviocgbit(struct input_dev *dev, |
| 807 | unsigned int type, unsigned int size, |
| 808 | void __user *p, int compat_mode) |
| 809 | { |
| 810 | unsigned long *bits; |
| 811 | int len; |
| 812 | |
| 813 | switch (type) { |
| 814 | |
| 815 | case 0: bits = dev->evbit; len = EV_MAX; break; |
| 816 | case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; |
| 817 | case EV_REL: bits = dev->relbit; len = REL_MAX; break; |
| 818 | case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; |
| 819 | case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; |
| 820 | case EV_LED: bits = dev->ledbit; len = LED_MAX; break; |
| 821 | case EV_SND: bits = dev->sndbit; len = SND_MAX; break; |
| 822 | case EV_FF: bits = dev->ffbit; len = FF_MAX; break; |
| 823 | case EV_SW: bits = dev->swbit; len = SW_MAX; break; |
| 824 | default: return -EINVAL; |
| 825 | } |
| 826 | |
| 827 | return bits_to_user(bits, len, size, p, compat_mode); |
| 828 | } |
| 829 | |
| 830 | static int evdev_handle_get_keycode(struct input_dev *dev, void __user *p) |
| 831 | { |
| 832 | struct input_keymap_entry ke = { |
| 833 | .len = sizeof(unsigned int), |
| 834 | .flags = 0, |
| 835 | }; |
| 836 | int __user *ip = (int __user *)p; |
| 837 | int error; |
| 838 | |
| 839 | /* legacy case */ |
| 840 | if (copy_from_user(ke.scancode, p, sizeof(unsigned int))) |
| 841 | return -EFAULT; |
| 842 | |
| 843 | error = input_get_keycode(dev, &ke); |
| 844 | if (error) |
| 845 | return error; |
| 846 | |
| 847 | if (put_user(ke.keycode, ip + 1)) |
| 848 | return -EFAULT; |
| 849 | |
| 850 | return 0; |
| 851 | } |
| 852 | |
| 853 | static int evdev_handle_get_keycode_v2(struct input_dev *dev, void __user *p) |
| 854 | { |
| 855 | struct input_keymap_entry ke; |
| 856 | int error; |
| 857 | |
| 858 | if (copy_from_user(&ke, p, sizeof(ke))) |
| 859 | return -EFAULT; |
| 860 | |
| 861 | error = input_get_keycode(dev, &ke); |
| 862 | if (error) |
| 863 | return error; |
| 864 | |
| 865 | if (copy_to_user(p, &ke, sizeof(ke))) |
| 866 | return -EFAULT; |
| 867 | |
| 868 | return 0; |
| 869 | } |
| 870 | |
| 871 | static int evdev_handle_set_keycode(struct input_dev *dev, void __user *p) |
| 872 | { |
| 873 | struct input_keymap_entry ke = { |
| 874 | .len = sizeof(unsigned int), |
| 875 | .flags = 0, |
| 876 | }; |
| 877 | int __user *ip = (int __user *)p; |
| 878 | |
| 879 | if (copy_from_user(ke.scancode, p, sizeof(unsigned int))) |
| 880 | return -EFAULT; |
| 881 | |
| 882 | if (get_user(ke.keycode, ip + 1)) |
| 883 | return -EFAULT; |
| 884 | |
| 885 | return input_set_keycode(dev, &ke); |
| 886 | } |
| 887 | |
| 888 | static int evdev_handle_set_keycode_v2(struct input_dev *dev, void __user *p) |
| 889 | { |
| 890 | struct input_keymap_entry ke; |
| 891 | |
| 892 | if (copy_from_user(&ke, p, sizeof(ke))) |
| 893 | return -EFAULT; |
| 894 | |
| 895 | if (ke.len > sizeof(ke.scancode)) |
| 896 | return -EINVAL; |
| 897 | |
| 898 | return input_set_keycode(dev, &ke); |
| 899 | } |
| 900 | |
| 901 | /* |
| 902 | * If we transfer state to the user, we should flush all pending events |
| 903 | * of the same type from the client's queue. Otherwise, they might end up |
| 904 | * with duplicate events, which can screw up client's state tracking. |
| 905 | * If bits_to_user fails after flushing the queue, we queue a SYN_DROPPED |
| 906 | * event so user-space will notice missing events. |
| 907 | * |
| 908 | * LOCKING: |
| 909 | * We need to take event_lock before buffer_lock to avoid dead-locks. But we |
| 910 | * need the even_lock only to guarantee consistent state. We can safely release |
| 911 | * it while flushing the queue. This allows input-core to handle filters while |
| 912 | * we flush the queue. |
| 913 | */ |
| 914 | static int evdev_handle_get_val(struct evdev_client *client, |
| 915 | struct input_dev *dev, unsigned int type, |
| 916 | unsigned long *bits, unsigned int maxbit, |
| 917 | unsigned int maxlen, void __user *p, |
| 918 | int compat) |
| 919 | { |
| 920 | int ret; |
| 921 | unsigned long *mem; |
| 922 | size_t len; |
| 923 | |
| 924 | len = BITS_TO_LONGS(maxbit) * sizeof(unsigned long); |
| 925 | mem = kmalloc(len, GFP_KERNEL); |
| 926 | if (!mem) |
| 927 | return -ENOMEM; |
| 928 | |
| 929 | spin_lock_irq(&dev->event_lock); |
| 930 | spin_lock(&client->buffer_lock); |
| 931 | |
| 932 | memcpy(mem, bits, len); |
| 933 | |
| 934 | spin_unlock(&dev->event_lock); |
| 935 | |
| 936 | __evdev_flush_queue(client, type); |
| 937 | |
| 938 | spin_unlock_irq(&client->buffer_lock); |
| 939 | |
| 940 | ret = bits_to_user(mem, maxbit, maxlen, p, compat); |
| 941 | if (ret < 0) |
| 942 | evdev_queue_syn_dropped(client); |
| 943 | |
| 944 | kfree(mem); |
| 945 | |
| 946 | return ret; |
| 947 | } |
| 948 | |
| 949 | static int evdev_handle_mt_request(struct input_dev *dev, |
| 950 | unsigned int size, |
| 951 | int __user *ip) |
| 952 | { |
| 953 | const struct input_mt *mt = dev->mt; |
| 954 | unsigned int code; |
| 955 | int max_slots; |
| 956 | int i; |
| 957 | |
| 958 | if (get_user(code, &ip[0])) |
| 959 | return -EFAULT; |
| 960 | if (!mt || !input_is_mt_value(code)) |
| 961 | return -EINVAL; |
| 962 | |
| 963 | max_slots = (size - sizeof(__u32)) / sizeof(__s32); |
| 964 | for (i = 0; i < mt->num_slots && i < max_slots; i++) { |
| 965 | int value = input_mt_get_value(&mt->slots[i], code); |
| 966 | if (put_user(value, &ip[1 + i])) |
| 967 | return -EFAULT; |
| 968 | } |
| 969 | |
| 970 | return 0; |
| 971 | } |
| 972 | |
| 973 | static int evdev_revoke(struct evdev *evdev, struct evdev_client *client, |
| 974 | struct file *file) |
| 975 | { |
| 976 | client->revoked = true; |
| 977 | evdev_ungrab(evdev, client); |
| 978 | input_flush_device(&evdev->handle, file); |
| 979 | wake_up_interruptible(&evdev->wait); |
| 980 | |
| 981 | return 0; |
| 982 | } |
| 983 | |
| 984 | /* must be called with evdev-mutex held */ |
| 985 | static int evdev_set_mask(struct evdev_client *client, |
| 986 | unsigned int type, |
| 987 | const void __user *codes, |
| 988 | u32 codes_size, |
| 989 | int compat) |
| 990 | { |
| 991 | unsigned long flags, *mask, *oldmask; |
| 992 | size_t cnt; |
| 993 | int error; |
| 994 | |
| 995 | /* we allow unknown types and 'codes_size > size' for forward-compat */ |
| 996 | cnt = evdev_get_mask_cnt(type); |
| 997 | if (!cnt) |
| 998 | return 0; |
| 999 | |
| 1000 | mask = kcalloc(sizeof(unsigned long), BITS_TO_LONGS(cnt), GFP_KERNEL); |
| 1001 | if (!mask) |
| 1002 | return -ENOMEM; |
| 1003 | |
| 1004 | error = bits_from_user(mask, cnt - 1, codes_size, codes, compat); |
| 1005 | if (error < 0) { |
| 1006 | kfree(mask); |
| 1007 | return error; |
| 1008 | } |
| 1009 | |
| 1010 | spin_lock_irqsave(&client->buffer_lock, flags); |
| 1011 | oldmask = client->evmasks[type]; |
| 1012 | client->evmasks[type] = mask; |
| 1013 | spin_unlock_irqrestore(&client->buffer_lock, flags); |
| 1014 | |
| 1015 | kfree(oldmask); |
| 1016 | |
| 1017 | return 0; |
| 1018 | } |
| 1019 | |
| 1020 | /* must be called with evdev-mutex held */ |
| 1021 | static int evdev_get_mask(struct evdev_client *client, |
| 1022 | unsigned int type, |
| 1023 | void __user *codes, |
| 1024 | u32 codes_size, |
| 1025 | int compat) |
| 1026 | { |
| 1027 | unsigned long *mask; |
| 1028 | size_t cnt, size, xfer_size; |
| 1029 | int i; |
| 1030 | int error; |
| 1031 | |
| 1032 | /* we allow unknown types and 'codes_size > size' for forward-compat */ |
| 1033 | cnt = evdev_get_mask_cnt(type); |
| 1034 | size = sizeof(unsigned long) * BITS_TO_LONGS(cnt); |
| 1035 | xfer_size = min_t(size_t, codes_size, size); |
| 1036 | |
| 1037 | if (cnt > 0) { |
| 1038 | mask = client->evmasks[type]; |
| 1039 | if (mask) { |
| 1040 | error = bits_to_user(mask, cnt - 1, |
| 1041 | xfer_size, codes, compat); |
| 1042 | if (error < 0) |
| 1043 | return error; |
| 1044 | } else { |
| 1045 | /* fake mask with all bits set */ |
| 1046 | for (i = 0; i < xfer_size; i++) |
| 1047 | if (put_user(0xffU, (u8 __user *)codes + i)) |
| 1048 | return -EFAULT; |
| 1049 | } |
| 1050 | } |
| 1051 | |
| 1052 | if (xfer_size < codes_size) |
| 1053 | if (clear_user(codes + xfer_size, codes_size - xfer_size)) |
| 1054 | return -EFAULT; |
| 1055 | |
| 1056 | return 0; |
| 1057 | } |
| 1058 | |
| 1059 | static long evdev_do_ioctl(struct file *file, unsigned int cmd, |
| 1060 | void __user *p, int compat_mode) |
| 1061 | { |
| 1062 | struct evdev_client *client = file->private_data; |
| 1063 | struct evdev *evdev = client->evdev; |
| 1064 | struct input_dev *dev = evdev->handle.dev; |
| 1065 | struct input_absinfo abs; |
| 1066 | struct input_mask mask; |
| 1067 | struct ff_effect effect; |
| 1068 | int __user *ip = (int __user *)p; |
| 1069 | unsigned int i, t, u, v; |
| 1070 | unsigned int size; |
| 1071 | int error; |
| 1072 | |
| 1073 | /* First we check for fixed-length commands */ |
| 1074 | switch (cmd) { |
| 1075 | |
| 1076 | case EVIOCGVERSION: |
| 1077 | return put_user(EV_VERSION, ip); |
| 1078 | |
| 1079 | case EVIOCGID: |
| 1080 | if (copy_to_user(p, &dev->id, sizeof(struct input_id))) |
| 1081 | return -EFAULT; |
| 1082 | return 0; |
| 1083 | |
| 1084 | case EVIOCGREP: |
| 1085 | if (!test_bit(EV_REP, dev->evbit)) |
| 1086 | return -ENOSYS; |
| 1087 | if (put_user(dev->rep[REP_DELAY], ip)) |
| 1088 | return -EFAULT; |
| 1089 | if (put_user(dev->rep[REP_PERIOD], ip + 1)) |
| 1090 | return -EFAULT; |
| 1091 | return 0; |
| 1092 | |
| 1093 | case EVIOCSREP: |
| 1094 | if (!test_bit(EV_REP, dev->evbit)) |
| 1095 | return -ENOSYS; |
| 1096 | if (get_user(u, ip)) |
| 1097 | return -EFAULT; |
| 1098 | if (get_user(v, ip + 1)) |
| 1099 | return -EFAULT; |
| 1100 | |
| 1101 | input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u); |
| 1102 | input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v); |
| 1103 | |
| 1104 | return 0; |
| 1105 | |
| 1106 | case EVIOCRMFF: |
| 1107 | return input_ff_erase(dev, (int)(unsigned long) p, file); |
| 1108 | |
| 1109 | case EVIOCGEFFECTS: |
| 1110 | i = test_bit(EV_FF, dev->evbit) ? |
| 1111 | dev->ff->max_effects : 0; |
| 1112 | if (put_user(i, ip)) |
| 1113 | return -EFAULT; |
| 1114 | return 0; |
| 1115 | |
| 1116 | case EVIOCGRAB: |
| 1117 | if (p) |
| 1118 | return evdev_grab(evdev, client); |
| 1119 | else |
| 1120 | return evdev_ungrab(evdev, client); |
| 1121 | |
| 1122 | case EVIOCREVOKE: |
| 1123 | if (p) |
| 1124 | return -EINVAL; |
| 1125 | else |
| 1126 | return evdev_revoke(evdev, client, file); |
| 1127 | |
| 1128 | case EVIOCGMASK: { |
| 1129 | void __user *codes_ptr; |
| 1130 | |
| 1131 | if (copy_from_user(&mask, p, sizeof(mask))) |
| 1132 | return -EFAULT; |
| 1133 | |
| 1134 | codes_ptr = (void __user *)(unsigned long)mask.codes_ptr; |
| 1135 | return evdev_get_mask(client, |
| 1136 | mask.type, codes_ptr, mask.codes_size, |
| 1137 | compat_mode); |
| 1138 | } |
| 1139 | |
| 1140 | case EVIOCSMASK: { |
| 1141 | const void __user *codes_ptr; |
| 1142 | |
| 1143 | if (copy_from_user(&mask, p, sizeof(mask))) |
| 1144 | return -EFAULT; |
| 1145 | |
| 1146 | codes_ptr = (const void __user *)(unsigned long)mask.codes_ptr; |
| 1147 | return evdev_set_mask(client, |
| 1148 | mask.type, codes_ptr, mask.codes_size, |
| 1149 | compat_mode); |
| 1150 | } |
| 1151 | |
| 1152 | case EVIOCSCLOCKID: |
| 1153 | if (copy_from_user(&i, p, sizeof(unsigned int))) |
| 1154 | return -EFAULT; |
| 1155 | |
| 1156 | return evdev_set_clk_type(client, i); |
| 1157 | |
| 1158 | case EVIOCGKEYCODE: |
| 1159 | return evdev_handle_get_keycode(dev, p); |
| 1160 | |
| 1161 | case EVIOCSKEYCODE: |
| 1162 | return evdev_handle_set_keycode(dev, p); |
| 1163 | |
| 1164 | case EVIOCGKEYCODE_V2: |
| 1165 | return evdev_handle_get_keycode_v2(dev, p); |
| 1166 | |
| 1167 | case EVIOCSKEYCODE_V2: |
| 1168 | return evdev_handle_set_keycode_v2(dev, p); |
| 1169 | } |
| 1170 | |
| 1171 | size = _IOC_SIZE(cmd); |
| 1172 | |
| 1173 | /* Now check variable-length commands */ |
| 1174 | #define EVIOC_MASK_SIZE(nr) ((nr) & ~(_IOC_SIZEMASK << _IOC_SIZESHIFT)) |
| 1175 | switch (EVIOC_MASK_SIZE(cmd)) { |
| 1176 | |
| 1177 | case EVIOCGPROP(0): |
| 1178 | return bits_to_user(dev->propbit, INPUT_PROP_MAX, |
| 1179 | size, p, compat_mode); |
| 1180 | |
| 1181 | case EVIOCGMTSLOTS(0): |
| 1182 | return evdev_handle_mt_request(dev, size, ip); |
| 1183 | |
| 1184 | case EVIOCGKEY(0): |
| 1185 | return evdev_handle_get_val(client, dev, EV_KEY, dev->key, |
| 1186 | KEY_MAX, size, p, compat_mode); |
| 1187 | |
| 1188 | case EVIOCGLED(0): |
| 1189 | return evdev_handle_get_val(client, dev, EV_LED, dev->led, |
| 1190 | LED_MAX, size, p, compat_mode); |
| 1191 | |
| 1192 | case EVIOCGSND(0): |
| 1193 | return evdev_handle_get_val(client, dev, EV_SND, dev->snd, |
| 1194 | SND_MAX, size, p, compat_mode); |
| 1195 | |
| 1196 | case EVIOCGSW(0): |
| 1197 | return evdev_handle_get_val(client, dev, EV_SW, dev->sw, |
| 1198 | SW_MAX, size, p, compat_mode); |
| 1199 | |
| 1200 | case EVIOCGNAME(0): |
| 1201 | return str_to_user(dev->name, size, p); |
| 1202 | |
| 1203 | case EVIOCGPHYS(0): |
| 1204 | return str_to_user(dev->phys, size, p); |
| 1205 | |
| 1206 | case EVIOCGUNIQ(0): |
| 1207 | return str_to_user(dev->uniq, size, p); |
| 1208 | |
| 1209 | case EVIOC_MASK_SIZE(EVIOCSFF): |
| 1210 | if (input_ff_effect_from_user(p, size, &effect)) |
| 1211 | return -EFAULT; |
| 1212 | |
| 1213 | error = input_ff_upload(dev, &effect, file); |
| 1214 | if (error) |
| 1215 | return error; |
| 1216 | |
| 1217 | if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) |
| 1218 | return -EFAULT; |
| 1219 | |
| 1220 | return 0; |
| 1221 | } |
| 1222 | |
| 1223 | /* Multi-number variable-length handlers */ |
| 1224 | if (_IOC_TYPE(cmd) != 'E') |
| 1225 | return -EINVAL; |
| 1226 | |
| 1227 | if (_IOC_DIR(cmd) == _IOC_READ) { |
| 1228 | |
| 1229 | if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) |
| 1230 | return handle_eviocgbit(dev, |
| 1231 | _IOC_NR(cmd) & EV_MAX, size, |
| 1232 | p, compat_mode); |
| 1233 | |
| 1234 | if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { |
| 1235 | |
| 1236 | if (!dev->absinfo) |
| 1237 | return -EINVAL; |
| 1238 | |
| 1239 | t = _IOC_NR(cmd) & ABS_MAX; |
| 1240 | abs = dev->absinfo[t]; |
| 1241 | |
| 1242 | if (copy_to_user(p, &abs, min_t(size_t, |
| 1243 | size, sizeof(struct input_absinfo)))) |
| 1244 | return -EFAULT; |
| 1245 | |
| 1246 | return 0; |
| 1247 | } |
| 1248 | } |
| 1249 | |
| 1250 | if (_IOC_DIR(cmd) == _IOC_WRITE) { |
| 1251 | |
| 1252 | if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { |
| 1253 | |
| 1254 | if (!dev->absinfo) |
| 1255 | return -EINVAL; |
| 1256 | |
| 1257 | t = _IOC_NR(cmd) & ABS_MAX; |
| 1258 | |
| 1259 | if (copy_from_user(&abs, p, min_t(size_t, |
| 1260 | size, sizeof(struct input_absinfo)))) |
| 1261 | return -EFAULT; |
| 1262 | |
| 1263 | if (size < sizeof(struct input_absinfo)) |
| 1264 | abs.resolution = 0; |
| 1265 | |
| 1266 | /* We can't change number of reserved MT slots */ |
| 1267 | if (t == ABS_MT_SLOT) |
| 1268 | return -EINVAL; |
| 1269 | |
| 1270 | /* |
| 1271 | * Take event lock to ensure that we are not |
| 1272 | * changing device parameters in the middle |
| 1273 | * of event. |
| 1274 | */ |
| 1275 | spin_lock_irq(&dev->event_lock); |
| 1276 | dev->absinfo[t] = abs; |
| 1277 | spin_unlock_irq(&dev->event_lock); |
| 1278 | |
| 1279 | return 0; |
| 1280 | } |
| 1281 | } |
| 1282 | |
| 1283 | return -EINVAL; |
| 1284 | } |
| 1285 | |
| 1286 | static long evdev_ioctl_handler(struct file *file, unsigned int cmd, |
| 1287 | void __user *p, int compat_mode) |
| 1288 | { |
| 1289 | struct evdev_client *client = file->private_data; |
| 1290 | struct evdev *evdev = client->evdev; |
| 1291 | int retval; |
| 1292 | |
| 1293 | retval = mutex_lock_interruptible(&evdev->mutex); |
| 1294 | if (retval) |
| 1295 | return retval; |
| 1296 | |
| 1297 | if (!evdev->exist || client->revoked) { |
| 1298 | retval = -ENODEV; |
| 1299 | goto out; |
| 1300 | } |
| 1301 | |
| 1302 | retval = evdev_do_ioctl(file, cmd, p, compat_mode); |
| 1303 | |
| 1304 | out: |
| 1305 | mutex_unlock(&evdev->mutex); |
| 1306 | return retval; |
| 1307 | } |
| 1308 | |
| 1309 | static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| 1310 | { |
| 1311 | return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); |
| 1312 | } |
| 1313 | |
| 1314 | #ifdef CONFIG_COMPAT |
| 1315 | static long evdev_ioctl_compat(struct file *file, |
| 1316 | unsigned int cmd, unsigned long arg) |
| 1317 | { |
| 1318 | return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); |
| 1319 | } |
| 1320 | #endif |
| 1321 | |
| 1322 | static const struct file_operations evdev_fops = { |
| 1323 | .owner = THIS_MODULE, |
| 1324 | .read = evdev_read, |
| 1325 | .write = evdev_write, |
| 1326 | .poll = evdev_poll, |
| 1327 | .open = evdev_open, |
| 1328 | .release = evdev_release, |
| 1329 | .unlocked_ioctl = evdev_ioctl, |
| 1330 | #ifdef CONFIG_COMPAT |
| 1331 | .compat_ioctl = evdev_ioctl_compat, |
| 1332 | #endif |
| 1333 | .fasync = evdev_fasync, |
| 1334 | .flush = evdev_flush, |
| 1335 | .llseek = no_llseek, |
| 1336 | }; |
| 1337 | |
| 1338 | /* |
| 1339 | * Mark device non-existent. This disables writes, ioctls and |
| 1340 | * prevents new users from opening the device. Already posted |
| 1341 | * blocking reads will stay, however new ones will fail. |
| 1342 | */ |
| 1343 | static void evdev_mark_dead(struct evdev *evdev) |
| 1344 | { |
| 1345 | mutex_lock(&evdev->mutex); |
| 1346 | evdev->exist = false; |
| 1347 | mutex_unlock(&evdev->mutex); |
| 1348 | } |
| 1349 | |
| 1350 | static void evdev_cleanup(struct evdev *evdev) |
| 1351 | { |
| 1352 | struct input_handle *handle = &evdev->handle; |
| 1353 | |
| 1354 | evdev_mark_dead(evdev); |
| 1355 | evdev_hangup(evdev); |
| 1356 | |
| 1357 | cdev_del(&evdev->cdev); |
| 1358 | |
| 1359 | /* evdev is marked dead so no one else accesses evdev->open */ |
| 1360 | if (evdev->open) { |
| 1361 | input_flush_device(handle, NULL); |
| 1362 | input_close_device(handle); |
| 1363 | } |
| 1364 | } |
| 1365 | |
| 1366 | /* |
| 1367 | * Create new evdev device. Note that input core serializes calls |
| 1368 | * to connect and disconnect. |
| 1369 | */ |
| 1370 | static int evdev_connect(struct input_handler *handler, struct input_dev *dev, |
| 1371 | const struct input_device_id *id) |
| 1372 | { |
| 1373 | struct evdev *evdev; |
| 1374 | int minor; |
| 1375 | int dev_no; |
| 1376 | int error; |
| 1377 | |
| 1378 | minor = input_get_new_minor(EVDEV_MINOR_BASE, EVDEV_MINORS, true); |
| 1379 | if (minor < 0) { |
| 1380 | error = minor; |
| 1381 | pr_err("failed to reserve new minor: %d\n", error); |
| 1382 | return error; |
| 1383 | } |
| 1384 | |
| 1385 | evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); |
| 1386 | if (!evdev) { |
| 1387 | error = -ENOMEM; |
| 1388 | goto err_free_minor; |
| 1389 | } |
| 1390 | |
| 1391 | INIT_LIST_HEAD(&evdev->client_list); |
| 1392 | spin_lock_init(&evdev->client_lock); |
| 1393 | mutex_init(&evdev->mutex); |
| 1394 | init_waitqueue_head(&evdev->wait); |
| 1395 | evdev->exist = true; |
| 1396 | |
| 1397 | dev_no = minor; |
| 1398 | /* Normalize device number if it falls into legacy range */ |
| 1399 | if (dev_no < EVDEV_MINOR_BASE + EVDEV_MINORS) |
| 1400 | dev_no -= EVDEV_MINOR_BASE; |
| 1401 | dev_set_name(&evdev->dev, "event%d", dev_no); |
| 1402 | |
| 1403 | evdev->handle.dev = input_get_device(dev); |
| 1404 | evdev->handle.name = dev_name(&evdev->dev); |
| 1405 | evdev->handle.handler = handler; |
| 1406 | evdev->handle.private = evdev; |
| 1407 | |
| 1408 | evdev->dev.devt = MKDEV(INPUT_MAJOR, minor); |
| 1409 | evdev->dev.class = &input_class; |
| 1410 | evdev->dev.parent = &dev->dev; |
| 1411 | evdev->dev.release = evdev_free; |
| 1412 | device_initialize(&evdev->dev); |
| 1413 | |
| 1414 | error = input_register_handle(&evdev->handle); |
| 1415 | if (error) |
| 1416 | goto err_free_evdev; |
| 1417 | |
| 1418 | cdev_init(&evdev->cdev, &evdev_fops); |
| 1419 | evdev->cdev.kobj.parent = &evdev->dev.kobj; |
| 1420 | error = cdev_add(&evdev->cdev, evdev->dev.devt, 1); |
| 1421 | if (error) |
| 1422 | goto err_unregister_handle; |
| 1423 | |
| 1424 | error = device_add(&evdev->dev); |
| 1425 | if (error) |
| 1426 | goto err_cleanup_evdev; |
| 1427 | |
| 1428 | return 0; |
| 1429 | |
| 1430 | err_cleanup_evdev: |
| 1431 | evdev_cleanup(evdev); |
| 1432 | err_unregister_handle: |
| 1433 | input_unregister_handle(&evdev->handle); |
| 1434 | err_free_evdev: |
| 1435 | put_device(&evdev->dev); |
| 1436 | err_free_minor: |
| 1437 | input_free_minor(minor); |
| 1438 | return error; |
| 1439 | } |
| 1440 | |
| 1441 | static void evdev_disconnect(struct input_handle *handle) |
| 1442 | { |
| 1443 | struct evdev *evdev = handle->private; |
| 1444 | |
| 1445 | device_del(&evdev->dev); |
| 1446 | evdev_cleanup(evdev); |
| 1447 | input_free_minor(MINOR(evdev->dev.devt)); |
| 1448 | input_unregister_handle(handle); |
| 1449 | put_device(&evdev->dev); |
| 1450 | } |
| 1451 | |
| 1452 | static const struct input_device_id evdev_ids[] = { |
| 1453 | { .driver_info = 1 }, /* Matches all devices */ |
| 1454 | { }, /* Terminating zero entry */ |
| 1455 | }; |
| 1456 | |
| 1457 | MODULE_DEVICE_TABLE(input, evdev_ids); |
| 1458 | |
| 1459 | static struct input_handler evdev_handler = { |
| 1460 | .event = evdev_event, |
| 1461 | .events = evdev_events, |
| 1462 | .connect = evdev_connect, |
| 1463 | .disconnect = evdev_disconnect, |
| 1464 | .legacy_minors = true, |
| 1465 | .minor = EVDEV_MINOR_BASE, |
| 1466 | .name = "evdev", |
| 1467 | .id_table = evdev_ids, |
| 1468 | }; |
| 1469 | |
| 1470 | static int __init evdev_init(void) |
| 1471 | { |
| 1472 | return input_register_handler(&evdev_handler); |
| 1473 | } |
| 1474 | |
| 1475 | static void __exit evdev_exit(void) |
| 1476 | { |
| 1477 | input_unregister_handler(&evdev_handler); |
| 1478 | } |
| 1479 | |
| 1480 | module_init(evdev_init); |
| 1481 | module_exit(evdev_exit); |
| 1482 | |
| 1483 | MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); |
| 1484 | MODULE_DESCRIPTION("Input driver event char devices"); |
| 1485 | MODULE_LICENSE("GPL"); |